Under Section 139(2) Companies Act 2013, mandatory rotation of audit firms applies to:

1. Section 139(2) Companies Act 2013 mandates AUDITOR ROTATION for listed companies and prescribed classes: no listed company or other prescribed class shall appoint or re-appoint (a) an INDIVIDUAL as auditor for more than ONE term of 5 consecutive years; (b) an AUDIT FIRM as auditor for more than TWO terms of 5 consecutive years. 2. After the maximum term, mandatory cooling-off of 5 years before re-appointment. 3. Rule 5 Companies (Audit and Auditors) Rules 2014 specifies: all unlisted public companies having paid-up capital ≥ Rs 10 crore; all private companies having paid-up capital ≥ Rs 50 crore; all companies having public borrowings ≥ Rs 50 crore. 4. Hence option B is correct. _Source: Companies Act 2013 (Act 18 of 2013), Govt. of India MCA — Companies Act 2013, Section 139(2); Companies (Audit and Auditors) Rules 2014, Rule 5_